Don't initialize an instance or static variable to its default value

src/site/resources/checkstyle/checkstyle.xml

@@ -36,6 +36,7 @@ limitations under the License.
     <property name="file" value="src/site/resources/checkstyle/checkstyle-suppressions.xml"/>
   </module>
   <module name="TreeWalker">
+    <module name="ExplicitInitializationCheck" />
     <module name="AvoidStarImport"/>
     <module name="IllegalImport"/>
     <module name="RedundantImport"/>

src/test/java/org/apache/commons/lang3/builder/DiffBuilderTest.java

@@ -54,7 +54,7 @@ public class DiffBuilderTest extends AbstractLangTest {
         private long[] longArrayField = {1L};
         private short shortField = 1;
         private short[] shortArrayField = {1};
-        private Object objectField = null;
+        private Object objectField;
         private Object[] objectArrayField = {null};
 
         @Override

src/test/java/org/apache/commons/lang3/builder/HashCodeBuilderTest.java

@@ -128,13 +128,13 @@ public class HashCodeBuilderTest extends AbstractLangTest {
 
     static class TestObjectWithMultipleFields {
         @SuppressWarnings("unused")
-        private int one = 0;
+        private int one;
 
         @SuppressWarnings("unused")
-        private int two = 0;
+        private int two;
 
         @SuppressWarnings("unused")
-        private int three = 0;
+        private int three;
 
         TestObjectWithMultipleFields(final int one, final int two, final int three) {
             this.one = one;

src/test/java/org/apache/commons/lang3/concurrent/BackgroundInitializerTest.java

@@ -306,7 +306,7 @@ public class BackgroundInitializerTest extends AbstractLangTest {
 
         /** A latch tests can use to control when initialize completes. */
         final CountDownLatch latch = new CountDownLatch(1);
-        boolean waitForLatch = false;
+        boolean waitForLatch;
 
         /** An object containing the state we are testing */
         CloseableCounter counter = new CloseableCounter();

src/test/java/org/apache/commons/lang3/concurrent/MultiBackgroundInitializerTest.java

@@ -439,7 +439,7 @@ public class MultiBackgroundInitializerTest extends AbstractLangTest {
 
         /** A latch tests can use to control when initialize completes. */
         final CountDownLatch latch = new CountDownLatch(1);
-        boolean waitForLatch = false;
+        boolean waitForLatch;
 
         public void enableLatch() {
             waitForLatch = true;

src/test/java/org/apache/commons/lang3/reflect/testbed/Parent.java

@@ -20,8 +20,8 @@ package org.apache.commons.lang3.reflect.testbed;
  */
 class Parent implements Foo {
     public String s = "s";
-    protected boolean b = false;
-    int i = 0;
+    protected boolean b;
+    int i;
     @SuppressWarnings("unused")
     private final double d = 0.0;